Mayhem & Monsters, & Time Travel
by The Social Monstrosity
Summary: (An Adventure Time Tale #3) An army from a not-too-distant future threatens to destroy Ooo's already fragile peace. However, they bring our favorite adventurer with them, shocking everyone involved. Although, our hero may not be as heroic as he once sought out to be. Rated T for action, sensual themes, and mild language.
1. Prologue: Not A Hero

Prologue: Not A Hero

 _When I discovered that I, Finnegan Hugo Mertens, was about to travel through time, my first thought was how I could fix every mistake I had ever made._

 _To save those I couldn't, to mend the hearts I broke, to bring justice to those who deserved it._

 _If I could change my past, I could live the life my younger self had always dreamed of living._

 _To be a savior._

 _To be a warrior._

 _To be a hero._

 _A hero._

 _Puff-fut, the only way my name and that word could be anywhere near each other is if a big fat NOT was plastered right smack in the middle._

 _I'm no hero._

 _I mean sure, I saved a few people here and there, stopped the world from collapsing onto itself once or twice._

 _But I'm no hero._

 _If I was, I would have done what was right. Cause that's what heroes do._

 _Problem was, I didn't know what was right. Still don't. All I know is that I made the wrong choice that day._

 _I'm no hero._

 _However, I know deep down, I can't change what happened. In order to find some shred of redemption, I need to live with my flawed past._

 _Still, I'm no hero._

 _If I was, even after my greatest failure, I wouldn't have turned my back on the people I cared for the most._

 _My friends._

 _My lover._

 _My family._

 _...my brother._

 _...I'm sorry Jake._

 _I am so, so sorry._

…

 _However, that can't stop me. It WON'T stop me. Not this time. Not now._

 _Not again._

 _I'm no hero._

 _But sometimes, you don't need a hero._

 _Sometimes, you just need someone who can get the job done._

 _And that, I am._

 _So with that…_

"YAAAAHHHHOOOOO!" I yelled, diving into the multicolored vortex.


	2. Chapter 1: Back Again, Sort Of

**Author's Note:**

 **{WARNING!} Be sure to listen to the song,** **(Busy Earnin'** **by "Jungle") when I give the go ahead. It really makes the intro that much better.**

 **If you happen to like the fic, please follow or favorite. If you want your opinion heard, write me a review or PM me.**

 **Now, ON WITH THE SHOW!**

 **Chapter One: Back Again, Sort Of**

Short of breath.

Sore all over.

Raging headache.

 _Pttf, "just a pinch" my a…_

"Finn!"

My thought was interrupted by a high-pitched voice screaming my name over and over again. Just what my headache needed.

"Finn! Finn! Wake up! Wake UP!" screamed the voice.

"Ugh," was all I could manage.

"Finn! Are you alright?" said the voice.

"Y… yeah. Just… give me a sec, okay?" I said, exhaustion evident in my tone.

Appearently, I landed on my back, with my torso facing upwards. Luckily, the soft grass I currently feel broke most of the fall. Although, unluckily, I also happened to have landed right on what felt like a tree root, which was now poking the sore of my back.

"Yeesh, you don't look so good." said the, again, incredibly high pitched voice.

"Gee, thanks for telling me, I wouldn't have known otherwise." I commented.

"Oh, reeeaal nice wise guy," She quipped, "come on, get off your lazy butt and get a move on. We are burning… err, night… light."

I raised my right eyebrow.

"Just get up." She said.

I say she, because my brain finally registered who exactly I was speaking to. _She_ was a certain smart mouthed, tech savvy, computer companion who always seemed to have my back. If only she wasn't so, what's the word? Oh yeah.

Annoying.

"Alright B-MO, I'm up." I said.

I finally open my eyes to see the darken sky above, which was dotted with several bright stars. Then, I look around to fine out we landed in the middle of a dense forest. All around me were trees that varied from tall and thin to short and stubby.

"Wow." I muttered.

"Right? We rarely see forests like these anymore." Chimed B-MO.

"Yeah. Shame." I said.

It really was breathtaking. I could see critters of various sizes scurry around, probably heading in for the night. All kinds of fruit were growing out of certain plants and bushes. You could actually smell the sweet aroma that was fresh air all around.

"Okay, enough sight seeing," exclaimed B-MO, getting my attention, "let's get going."

"Right," I said, still exhausted.

I slowly rise to my sore feet, which I noticed were completely bare. I then take a sec to fully asset the situation. First, I bring the green-tinted, gauntlet-like contraption planted on my left arm closer to my face, only to see BMO's pixelated face on its front screen.

"B, real quick, prepare a scan of the surrounding area, see where we are." I say.

"Okay." She happily complied.

I push the [release] button on the side of the "B-Go" that opened the slot right below it. What popped out was a small box with a few buttons here and there. I push the right sequence that transformed it into a mini-version of B-MO with bird-like wings. I then gently throw it into the air, to then see it hover a few feet away from me.

"B, set it to one-and-a-half clicks. Don't want it going too far, just enough to know where we ended up. Include any landmarks in the search."

"Got it!" exclaimed B-MO.

"Good." I said.

After I see the bot fly off into the distance, I look back at myself. At the moment, I was wearing what PB assigned me, which was basically a black and blue muscle shirt and a pair of pure-blue cargo pants that felt a little too tight. While the B-Go sat on my left forearm, my right one was wrapped in a long blade of grass.

"Tell me again why I had to wear this." I asked.

"Because Finn, Bubblegum specifically stated that all non-organic material would be vaporized, unless, properly contained, when entering. She had those made entirely out of cotton so you didn't have to come buck-naked." She said, giggling that last part.

"Pfft, are you kidding me? She only said that 'cause she saw it in some old cheesy time travel flic. P had no idea what was going to happen when we jumped through." I pouted.

"Oh, quiet you." She joked, "You're just mad because she didn't give you a goodbye kiss."

"Not funny." I deadpanned.

"No, it's completely funny." She joked.

"(sigh) Sure it is." I complained.

It's then that I did a quick look around, only to realize that something essential was missing.

"Uh, B?" I question.

"Yeah Finn?" Said B-MO.

"Where's the bag?"

Her face twisted into one of confusion, which was really starting to freak me out.

"What?" Was all she said.

"You know, the bag with all our gear!" I screamed.

"…oh." She exclaimed, "I don't know."

"Wha… what do you mean 'I don't know'!? We brought it with us through the portal! It should be here!" I screamed, again.

I spent the next half-hour searching frantically for our gear, only to come up with squat.

"Uh! PB's gonna kill us!" I exclaimed.

"No, just you." She said, "You where in charge of it."

Before I could teach the little smart-ass a lesson, B's mini-bot came back, indicating that it had completed its search. I grabbed it from mid air and practically jammed it back in its slot, irritated that all our essentials were nowhere in sight.

"Scanning… and don't be so rough!" B-MO said.

"Just tell me where we are. Like you said, we're 'burning night light'." I half-heartedly teased.

"Hmph," she pouted, "give me a sec."

Her face on the screen temporarily changed into a loading bar, which in my opinion was going (purposely) way too slow.

After a long thirty seconds, B-MO's face appeared on the screen.

"Scan complete," she stated, who then gave me a genuine smile, "We're in luck. My mini-bot spotted the Candy Kingdom not 1,326 m (or 1,450 yards) to the northwest of us."

"Good. At least we know **where** we were." I said.

Now all we got to do is find out **when**.

"Yep, **{Start Music Now!}** now let's get a move on!" She yelp in glee.

"Alright. Let's go." I said under my breath.

That's when we started our journey. Our quest. Our job.

While I begin our long walk to the City of Sweets, I look up into the sky, just thinking of all the trouble that lies before me.

It'll tough. No mistake.

There'll be confusion, mistrust, fighting, running, mayhem, acrobatics, gunfights, magic, womens, meatheads, trickery, swordplay, betrayal, love, suspense, moneymaking, fistfights, cheering, advance technology, tears, hover-boards, yelling, monsters, sweet threads, and of course…

…time travel.

And I can't wait.

 **Mayhem & Monsters, & Time Travel**

 **By the Social Monstrosity**

 **Enjoy the rest of the song.**


	3. Chapter 2: An Interesting Conversation

Author's Note:

…

…

…

… ehh, not much to say.

NOW, ON WITH THE SHOW!

Chapter Two: An Interesting Conversation

(Finn and Jake's Tree House)

Finn's first sight was the blinding light showing through his window. He blinked several times in order to regain his sight, only to be surrounded by the usual; messy bedroom, swords and other weapons scattered to all four corners of the room, and his canine brother snoring happily, all-the-while scratching his butt absentmindedly.

 _Same ole', same ole'._ He merrily thought.

He rubbed whatever sleep remained from his crust-filled eyes and began to shake the covers off of his still-sore extremities.

 _Man, who knew dungeon crawling for sixteen hours straight was a_ _ **bad**_ _idea._ Finn thought.

He then strode towards his wardrobe, having already bathed himself twice the night before. He shuddered at the lingering feeling of slim covering his garments.

 _So… much… gunk._ He thought.

Shaking that nasty image from his mind, he dressed in his usual attire of a sky blue shirt, deep blue shorts, his signature bear-hat, and a pair of all-black converse.

Since his backpack and other equipment had to be repaired, he had promised himself to take it easy for a little while.

 _How can I though,_ he thought to himself. _Tomorrow's the big day. Who knows what could go wrong._

He pushed the thought back, believing it to be unhealthy thinking of such disasters. Today, Finn was going to have a peaceful day.

No fighting, no bickering, and NO adventuring. Period.

"Yeah, right." Finn said aloud.

"What was that?" called a voice drowned in sleep.

It was none other than Jake, Finn's stepbrother and life-long companion, waking up from his deep slumber.

"Nothing buddy, just thinking about today… and how it's gonna suck." Finn mumbled.

"Dude, you need to chill, alright," Jake mock-scolded, magically stretching himself out of his bed, "We've been running around from job to dungeon 24/7 for three weeks straight, okay. We, and by that I mean you, need to calm the funk down, and relax."

"Huhh, I know." Finn sighed in defeat.

For the next couple of moments, the brothers made their way towards the kitchen, ready to eat some good ole' fashion breakfast.

"It's just," Finn started up again, "whenever I stop occupying my mind with adventuring junk, it starts to… wonder, ya know?"

"Ooohhh," Jake smugly said, while warming up a pot of hot water, "and does the meeting tomorrow have anything with this?"

Finn could only role his eyes at Jake as he took his seat at the table.

"Come on Jake," Finn complained, "Don't tell me you can't only imagine what could happen at the summit. I mean, for Glob's sake, we could be looking at total war here."

"Wow, wow, wow. You don't know that. For all we know, the entire thing could blow over in a matter of minutes." Jake reasoned.

"Bro, when have we ever been that lucky? You know how wonked out FP's brother is. I bet that ever since that nut became the new Flame King, he's devoted every moment and resource to bringing all the kingdoms to their knees. If it wasn't for PB's annual summit, we'd already be knee deep in scorching lava." Finn rambled.

"Oh, come on Finn, FP's brother isn't that nut up," Jake argued, "And even if he was, he'd have to get all the other kingdom's on his side before even thinking of going up against Bubblegum."

"Yeah, but let's face it, even before she got dethroned… and uh, re… throned, she wasn't exactly the most 'well-loved' person in the world." Finn countered.

"Says you." Mocked Jake.

"Hey! You… you know what I mean." Stumbled Finn.

"Yeah, yeah." Jake joked.

Finn rolled his eyes for what felt like the hundredth time, and it wasn't even noun yet. Jake poured the hot water into his cup, and churned it with his favorite tea mix, all the while Finn starred out the nearest window and saw the fields of grass he was so accustomed to seeing. His face then fell into a blank stare, before sighing at the stress of things.

"I'm… I'm just… scared Jake." Admitted Finn.

Almost spilling his cup's contents onto himself, Jake stared at the young teen, surprised that Finn, THE Finn Mertens, was afraid of something, let alone **admitting** it in the first 'sphere-in* place.

"I'm scarred… that things are gonna change, and not for the better." Continued Finn.

Jake then gathered himself, and strode over to the depressed boy. Finn nearly jumped when he felt a hand lightly pat his shoulder, only to see Jake's face next to his, giving him a gentle, almost fatherly, smile.

"Don't worry buddy," said Jake, "whatever does happen, whether FB's wacko brother does invade, or Glob, if the whole Nightosphere comes-a-knocking… you won't have to do it alone. Okay brother."

After what seemed like an eternity, Finn finally returned the smile with an even bigger one.

"Yeah man." exclaimed Finn.

"Adventure Time?" asked Jake, lifting his right fist into the air.

"Heh, Adventure Time." Said Finn, who then raised his left fist and collided it with Jakes, signaling their brotherly bond.

"Besides, how bad could it be?" Mocked Jake.

"…dude, did you **really** just say that?" Deadpanned Finn.

"What?" Said Jake, who saw nothing wrong with his last ominous statement.

All Finn could do was stare at his oblivious brother walk away while sipping his tea. Finn then looked back at the table and, seeing as how there wasn't any food currently placed on it, walked over to the fridge, all the while thinking to himself,

 _Eh, he's probably right. How bad could it get._

"Hey Finn! Let's head over to the Candy Kingdom later…

(Forest: Candy Grove)

"'ACHOO!'" I sneezed.

"You alright Finn?" questioned B-MO.

"Fine. I think its just allergies." I replied, bringing her up to my face, "By the by*, are we almost there? My feet are killing me."

 _Note-to-self, find a pair of shoes._ I thought. We had been walking nearly all mourning trying to reach the Candied City, though having no gear and thin-layered clothing made me feel almost… naked. And not in a good way.

I could hear B mutter something about me being an impatient jerk-wad (whatever that means), though I just ignored her. I wasn't really in the mood for bicker… ing.

Wait, didn't I just use that word a minute ago? Hm…

"Finn." B-MO said, "Finn! FINN!"

"Wha…" I slurred.

"(Sigh) It is happening, isn't it?" she asked.

"What do you mean?" I asked, confused out of my wit.

She sighed, this time in annoyance, which, I got to admit, kind of pissed me off.

"Didn't you pay any attention to QB?" She asked.

"(Pfft), you know I don't listen to her anymore." I replied, "Besides, after hearing her rattle on about paradoxes and multiple time lines [ _and_ _ **especially**_ _after debating which cheesy time travel movie was better],_ my brain was totally fried. I mean, come on! The one with the killer robots was obviously better! But no! All I hear is 'hover board' this and 'getting back to the future' that! COME ON!"

After a moment, I noticed B-MO giving mean this odd look out of the corner of my eye.

"What?" I asked impatiently.

"Well, before you went on your crazy rant," she explained, "I was going to say, that you're experiencing 'back-lash'."

"And… that's suppose to make sense… how?" I reply.

"(Sigh) It **means** that whenever you're in the same time period as your younger or older self, you'll start to think the same things they are and vice-a-versa." She continued. "So if the younger you thinks something, then you think the same thing, it'll feel like deja vu. Do you get it?"

 _Ow ow ow ow. Headache… overload!_

"Barely." I said through gritted teeth. "So… are we almost there yet?"

Before she had a chance to sigh yet again, the tall tower of the Candy Kingdom came into view. Which, of course, meant only one thing.

 _Here comes the migraine._

 **Author's Notes:**

 **There we go! Another one down!**

 **By the way, "'sphere-in" is a slang I came up with [Short for Nightosphere], and I meant to put the by* there since it's a habit of mine, like,**

" **By the by, could you get me a soda?"**

 **Like that.**

 **If you happen to like my little story, favorite and/or follow it.**

 **If you want your opinion heard, send me a review or PM me… or both!**

 **See ya** next **time!**


	4. Chapter 3: Kingsman Quote

Chapter Three: Are We Gonna Stand Around Here All Day, Or…

(Candy Kingdom: Princess Bubblegum's Chambers)

Twenty-six hours.

That was all Princess Bonnibel Bubblegum had. Twenty-six 'spherein hours before it all hits the fan. Before everything she knows and holds dear will be burned to the ground, literally, along with half the basted kingdom.

So as you can probably tell, she wasn't really in the best of moods.

"WHERE IN THE NAME OF GLOB IS! MY! HAIR BRUSH!" she screamed.

At the moment, she had held herself up in her room in order to concentrate on some form of solution to quell this **stupid** revolt. Since she didn't feel like putting on any formal clothes, she had left her sleep attire on, which consisted of a pink, spaghetti-string tank-top, loose grey sweats, and a pair of black-rimmed glasses that sat right on the bridge of her nose.

 _I am suppose to find some sort of way to stifle a life-long grudge with one of the most volatile races known to Ooo, and I can't even find a stupid hair accessary! Thank Glob for the summit._

It was true. It was all on her to put the Fire Kingdom at ease, since their newly appointed Fire King was against her and her entire kingdom.

 _And all because I said no to a stupid date._

She then let her entire body flop onto her soft bed, muttering on about due dates and "stupid" arguments.

 _It's strange though,_ she thought to herself, _I can't rap my head around the fact that this dingus became fire king in the first place. I thought Phoebe had that position filled already._

A much darker thought then crossed her mind.

 _I wonder if he did anything to her. Her kind does tend to be… well,_ _ **sinister**_ _at times, at least to a point. I hope she's okay._

That wasn't the only thing that was on her mind. Apparently, the other princesses, and basically anyone of royal importance, got themselves a legion of bodyguards all around them at all times. Not only that, these guards had come from some sort of mercenary band that just popped up out of nowhere.

These guys weren't any run-of-the-mill brutes, either. She had seen some, and even met a few in person, whenever she traveled to other kingdoms. Highly trained, heavily equipped, and unnervingly silent. Not a word was said between themselves, not one, and yet they walked around in large numbers with no problems whatsoever. Plus, they always had a helmet or hood over their heads at all times, not once showing what was underneath.

It was all quite strange really, even for Ooo.

Shaking her head of any more negative thoughts, she stood up from her bed, and, with a newly acquired determination… slumped onto the solid floor.

 _Where's a hero when you need one._ She thought to herself.

At that moment, someone began to knock on the door.

"Hey princess," called a Banana Guard, "Finn and Jake are here to see you!"

 _Oh, speak of the devil._ She thought.

In all honestly, she was relieved to have some company, especially since it was her two favorite heroes. She rarely said it anymore, but those two really were her best comrades, besides Marceline or course, but that was a whole other thing altogether. These two always seem to be by her side, no matter what, which was weird. She couldn't think of a reason why those two always helped her out a her jams.

 _Yes you do,_ said a voice in the back of her head, _the kid's hopelessly in love with you, and the dog likes to make fun of him for it._

 _Oh yeah,_ she giggled, _that's why._

"Okay! Tell them I'll be out in a minute!" she yelled outside her door.

"Ok! They said to meet them in the throne room!" yelled back the Banana Guard, who then went off to do his regular duties.

 _Hm, should I get something better on,_ she thought, _Nah, they won't mind. It's just Finn and Jake._

After pulling her hair into a loose ponytail, she then made her way downstairs to the throne room. However, when she got there, there wasn't a soul in sight. Plus, she couldn't remember it being this dark either. She looked around to see all the blinds shut, barely letting in any sunlight. Not only that, but there also wasn't a guard in sight.

 _That's odd,_ she puzzled, _where are they?_

"Finn!" she yelled out, "Jake! Where are you guys!"

Not a single reply was heard, which was really starting to freak her out.

 _Something's not right,_ she thought.

It was then that she made a made dash for the set of double-doors that led outside. Her hand had just landed on the nob when all of a sudden,

 _THWACK!_

While she lay on the floor nearly unconscious, PB heard someone say aloud,

"Wow! Dang, you almost killed her! Hehe, shame." Said a rough male voice, "Tie her up."

She felt a pair of large hands tie her hands and ankles up while another tied a gag around her mouth. She tried to look up at the individuals her were currently manhandling her, but she ended up getting a boot to the cheek instead.

"Hey bubble-butt," said the voice, who chose to speak right into her ear, "until I tell you to look at me, or anything for that matter, you'll be a nice little princess and keep your head to the ground. Got it?"

She didn't give him a response. Instead, she decided to give him a good ole' fashion head butt to the nose.

"GAH!" the man yelled, "Why you…!"

He was about to give her what she believed another foot to the face, when, all of a sudden, he began to eerily laugh his head off.

"Hehehahahhhaaha! Oh, man! What a FIRE you have! Hehehehahaha," cackled the man.

He then walked closer to her, saying something that sent chills right to the core of her soul.

"All the more reason to…" he grab her hair by the root and brought it up to his, " **snuff it out.** "

The man turned out to be a grass ogre, though he seemed to have a disease of some kind, as a strange black tar coated a good chunk of his body. He also looked like he was well aged, as the grass on his head and arms had a brownish tint to it. He wore a pair of armor-clad camo pants and some black combat boots that ended right below his knees.

"Alright boys," he called to the people behind her, "Let's bring her to the boss. I'm sure he'll love to see the booty we brought back with us."

He chuckled at his own joke, though the people behind her didn't seem to get it, since they didn't make a sound.

As one came into view, PB was shocked to see one of the same mercenaries she was thinking about not a minute ago. This meant many things, one of them being that the other princesses were in danger, and that the only person who knew, which was herself, was being carted off to Glob knows where.

At that moment, one thought popped into her head.

 _Someone! Anyone! Save me!_

 _CRASH!_

Having been turned around, she saw the person who had just broke through one of the windows. However, if her eyes wereserving her right, it appeared to be a blond, twenty-something year-old- **human** man in a blue/black muscle shirt, a pair of pure blue cargo pants, and had a device on his left hand that looked like a green gauntlet with a computer screen in the middle.

The man, who at this point was on one knee, slowing stood up. His fierce gaze scanned the room, taking in his surroundings. However, when it finally landed on her, it intensified. He then closed his eyes while simultaneously popping his neck. He then began to crack his knuckles one at a time, signing that it was, indeed, on

"Well," he finally said, his low voice laced with venom, "Are we gonna stand around here all day, or…" his mouth twitched upward to form a slight smirk

"…are we gonna fight."


End file.
